Railway car truck bolster



Dec. 25, 1934.

T. vH. SYMINGTON RAILWAY CAR TRUCK BOLSTER Filed Oct. 27, 1930 2 Sheets-Sheet l Dec. 2.5, 1934. H SYM|NGT0N 1,985,469

l RAILWAY CAR TRUCK HOLSTER Filed Oct. 27, 1950 2 Sheets-Sheet 2 J7 l/ i gli a 55* sie a@ Patented Dec. 25, 1934 UNIT-ED vSTATES PATENT OFFICE vThomas H. Symingtom to T. H. Symington &

Baltimore, Md., assigner Son, Inc., Baltimore, Md.,

a corporation of Maryland 1 Application October 27 "2s claims.

The invention relates t'o railwaycar trucks and has special reference to the 'bolsters'thereoi The principal yobject 'of the invention, generally stated, is to provide -a novel and vimproved r54 bolster for vrailway car trucks, particularly for use in or to form va partiof a Atruck of that type in which the spring .plank is eliminated, for ex ample .as disclosed inmy Vco-pending application for patent for Railway .car trucks, filed July 31, 1930, Serial No. 472,@116.

Generally speaking andby'way of introduction, it should be remembered that by eliminating the spring plank a railway'car truck can be greatly reduced in weight .andthe cost Vcan be decreased owing to fthe Yfact that kthere is one less 'part' necessary. Furthermore by eliminatingv `the spring plank there isno fdangerxof cooking or tilting the side frames with respect 'to' eachother as the result of 'manufacturing `variations in the length of holsters supposed to beuniform in size. In addition, the elimination of .the spring plank makes it possible to use abolster of greater depth than what vis considered the A. fR..A-. standard so that greater'st'rength with less Weight' may be had. Of course with the lelimination of the spring plank it'isquite apparent that' thebolster then becomes the only element which holds the' side framessquare. yIt 'is therefore proper that the bolster be made'suiiiciently strong to take any twisting strains which might come uponit, that its column engaging .lugs be increased in area to give a greater :bearing against rthe side frame for reducing the wear, and that adequate means be provided cooperating with 'the side frame andthe bolster for holding them in the proper relativepositions. These features are dis-- cussed in said coep'ending application but are repeated here for the sake lof clearness.

lt is with all of the foregoing facts and conditions in viewr that I have divised the present invention which has ioran important objectthe provision of a bolster which'isnot limited for use in a truck of thespringplankless type and which will possess the maximum strength throughout and therefore capable of successful and prolonged use in trucks beneath Ahigh capacity cars.

Another object of the invention isto providea truck bolster -of `the cast type in'which the various component parts, surfaces, angles and curves are so related as to produce a--bolster having what may be considered the maximum strength for resisting cantilever strains and withstanding transverse loading Without any danger of buckling at anypoint -or points, and that, too, While reducing the` Weight by judicious'coring and re 1930, serial No. 491,576 (o1. s-23o) duction of the thickness of the metal at neutral points, the ultimate result of the novel design being greatly increased strength with decreased weight. l

Another object ofthe invention is toprovide a bolster of this character I'which is adapted vto be used in connection with the conventional type of center plate Vand side bearings, the former being received within a center bearing of ordinary design except in so far as its-bracing is concerned and the latter being adapted to be mounted upon the top of the'bolster as is customary. f

Another object of the invention is toprovide a bolster having its ends so constructed that the coacting side frames may be removed Aby pulling them directly outward Without lowering the bolster.

Another object of the invention is to provide a bolster having its ends so constructed that the outside guide lugs are removable.

Another object of the invention is to-y construct a bolster so that, upon cooling of the metal after pouring, the cores may be so arranged that, as the cooling strains lare applied, the cores may yield through openings provided on the neutral axis of the bolster, thus reducing Vfoundry losses due to cooling cracks often appearing in bolster castings. l

yAnother object of the invention is to'provide a bolster which, if made of a depth whichwill not cause it to interfere with the spring plank, may be used in an ordinary type of truck in'which the spring plank is notfeliminated.

Yet another object is tc provide a bolster which will notcost more'to produce than one of ordinary design 'and'which in addition to the points of advantage above stressed will be a distinct improvement in the art.

VTo the attainment of the vforegoing and other objects and advantages, .the inventionpreferably consists in the detailed construction, combination, location and relative positions of bodyelements, walls, surfaces, reinforcing ribs, Webs and the like to be hereinafter more fully describedand claimed, andillustrated inthe accompanying drawings in which:

Figure l yis a top plan view of a portion of a bolster constructed in accordance with my invention, one end beingbroken away as both are the same,

Figure 2 is a central vertical longitudinal section taken on the line 2---2Av of Figure 1,

Figure 3 is a vertical crosssectional View taken on the'line 3 3 of Figure .2,

bolster as clearly indicated in Figure 3.

Figure 4 is a cross section taken on the line 4-4 of Figure 2,

Figure 5 is a similar view on the line 5-5 of Figure 2,

Figure 6 is an end elevation,

Figure '7 is a fragmentary horizontal section on the line 7 7 of Figure 2.

Referring more particularly to the drawings I have shown the bolster as conforming in some respects to the usual practice in so far as the generall shape is concerned, the features of radical departure being structural and internal. This bolster is formed in one piece as a casting and comprises an elongated body including a top wall 10, a bottom 11 and sides 12, the bottom being of less width than the top and the sides sloping upwardly and outwardly so that the body will be trapezium shaped in cross section. The top' 10 of course constitutes a compression member while the bottom 11 constitutes a tension member. The top is substantially horizontal throughout its major portion but inclines upwardly to a slight extent toward the center bearing which may be the usual upstanding circular flange 13 and which is adapted to receive and cooperate with the ordinary type of center plate which depends from the body bolster, not shown. The bolster is of maximum depth at its center and the bottom l1 inclines or slopes upwardly from the center to the point 14 from which it extends horizontally, the resultant end portion 15 being consequently of much less depth so as to conform substantially to the general standard and so that the usual nest of truck springs, not shown, may be engaged beneath the end within the window opening of the side frame, not shown. Other details in regard to the cooperation of the bolster with the side frame will be given later on.

At its center the bolster is preferably of greater depth than the standard. this being permissible for the reason that in a truck in which the spring plank is eliminated the increased depth will not cause any interference such as would take place if a plank were present. The bottom wall 11 is rather gently curved at the portion of maximum depth, as clearly shown. To provide strength and rigidity at the center where the weight is borne, I provide a spool-like construction involving an upright tubular thrust member 16 here disclosed as elliptical in cross section with its major axis lying along the longitudinal center line of the bolster. This thrust member merges into the top wall of the bolster within the confines of the ring 13 and merges at its lower end into the bottom of the bolster, it being preferable at the latter mentioned location to provide a plurality of triangular webs 17 which merge into the exterior of the thrust member and into the bottom of the bolster. There are also provided horizontal webs 18 which merge into the exterior of the member 16 and into the sides 12 of the The member 16 is additionally strengthened by an yinternal transverse web 19 at the transverse edges of which are upstanding ribs 20 between which are webs 21. There is no necessity for the Wall of the thrust member 16 to be solid and I have therefore shown it provided, above and below the transverse member 19, with openings 22 and 23 respectively which are judiciously proportioned so as to decrease the weight without sacrificing strength, this skeleton-like construction being really preferable to solid in accordance with sound principles of foundry practice.

Within the confines of the ring 13 which con"l stitutes the center bearing the top wall of the bolster is formed-with an opening 24 around which the metal is thickened upwardly and downwardly as at 25 and 26 for the sake of strength, the purpose of the opening being to receive the king pin, not shown, ordinarily provided at the middle of a center plate. While it may not be vitally necessary thev partition member 19 is shown as provided with an opening 27 and the center of the bottom of the bolster is shown as formed with an opening 28 which will permit the escape of any water which might by any chance enter within the member 16 and cause rusting out thereof.

As the compressive strains on the bolster are highest at that area adjacent the ring or flange 13 where the latter approaches the sides of the bolster, I preferably provide the top wall 10 with upstanding ribs 29 located at this area, these ribs rising from the bolster top at some little distance from the ring, converging toward the interior thereof, and merging into its periphery, the purpose of the ribs being to divert the high compression strain which works down the top edge of the bolster and to deflect a part of this strain into the center plate ring 13.

In order to reduce the weight, I have shown the top of the bolster as provided near the ring 13 with an elongated opening 30 extending longitudinally, the metal on the underside of the top wall l0 being thickened at the edges of this opening to form a bead 31 acting as a reinforcement so that greater stiffness will be had. Likewise at the reduced end portion 15 the top wall is formed with an opening 32 here disclosed as of triangular shape with the metal thickened at the underside of the top and around this opening to provide a reinforcing bead 33 which is likewise continuous. For a similar reason the bottom of the bolster is shown as provided, substantially in line beneath the opening with an opening 34, the metal at the inner surface of the bottom wall being thickened at the edge of the opening to define va stiffening bead 35.

For additionally decreasing the weight and also improving the structural characteristics of the bolster, the opposite sides are preferably formed at the center or opposite the openings 23 in the thrust member 16 with openings 36, and adjacent but outwardly ofthe thrust member 16 with other openings 3'7. The openings 36 and 37 extend downwardly fairly close to the bottom of the bolster but have their upper edges terminating considerably below the top thereof. The bottom is preferably of greater thickness than the sides, at least the major portion of the sides, and the material of the bottom is continued on up to form thickened portions 38, or ribs as they may be called, at the lower edges of the openings 36 and 3'7, it being noted that these ribs are continuous and that they merge at their ends into thickened portions or beads 39 which extend about the outer ends of the openings 37 and along the upper edges thereof, these beads 39 being continuous and extending across the center of the bolster, or in other words along the top of the openings 36. The portions of the material above the openings 37 will constitute compression members in the same sense as the top of the bolster and as it is known that compression members buckle if they are unduly long I reduce the length of these portions by increasing the depth of the side walls diagonally downward from the points 40 and 4l, the downward prolongation of the material between the ribs 39 and the'thrustfmember 16 being :indicated-at 42. vFurthermore as it is known that 'wherever -a change in'direction Atakes place `in a tension or compression 'member -secondarystresses are set up unless the member is braced against theadjacent members at the points of direction change, I provide curves 43 and 44 of relatively large radius'at the inner ends of the openings37. -Inother words at the lower inner corners of the openings 37 the side walls have extensionsv45 functioning in the same manner as the above mentioned extensions .42, the extensions 42 and 45 both merging into the .vertical side lwall tie. The Aprovision of these extensions 42f-and 45 has the effect of shortening lthe beam length of the metal above the openings y37 so that compression strains at this locality will bem'ore I effectively :counteracted or resisted, this being advisable as rthepoint lof tangency of the convex tension side Awith the upwardly inclined tension member -is :a considerable distance off-center with respectto the vertical axis ofthe bolster.

' As the `stress on the top of .-the'bolster is-.greate est atfthe upper longitudinal edges I have found it preferable Vthat .these Aedges lor l'corners be rounded off atra rather `gentle curvature, atleast at vthe intermediate lportion :of the bolster, as clearly indicated at 446 in Figure-this vincrease in curvature giving a greater surface area to resist the stress. Throughout the :intermediate ,portion .of the bolster, that -is to 4say up 'to-near the ends `15, the meta-l at these upper .longitudinal edges or corners is appreciably thickened, as shown at` 47 by the `simple expedient of providing upwardly converging beveled-surfaces 48 lonthe inner `faces 'ofthe side walls mergingin-to downwardly and-outwardly .beveled surfaces 49 on the underside'of the top fwall, rhebeveling lon the underside of the top is `shown as lomitted tat the lines `of sections 3-3 and 5-5,as.at thesefpoints the metal is thickened by bosses. Reinforcement of the lower edges :of the bolster is effected by a bevel on the Aside wall providing increased thickness/as at'481. This 4bevelinginside thebolster reinforces it, particularly `the I'end 'portions thereof, atY its most critical :pointsfor deilectionyof the ends which 'usually `deiiect at the points i4 where the `upwardly vand Ioutwardly tapering bottom portions merge into the vertically reduced end portions.

At a plurality of points theysides have small holes 50 therethrough. and surroundingthem the metal is thickened to provide bosses 51. Beneath the triangular openings 32 near the ends the bolster may be provided in its lbottom'with other smalllholes 52 for the reception of vprojections formed on `the coacting face of spring-nests.

It is intended that the bolstervbe equipped-'with side vbearings of conventional'design and Athough they are not illustrated, the `bolster is shown as provided in its top with aplurality of fholes 53 for. the reception of vwhatever securing elements, generally rivets, are used for fmountingthe side bearings. About these holes-the :metal .of .the top is thickened at its underside tofprovidereinforcing beads 54 compensating for the reduction in metal caused by the provision yof .the holes. As it is o uite obvious that considerable compression strainis exerted upon the .top wall Yof athebolster at the areas beneath the side bearings, I have shown each endportion of the bolster as'provided with an upstanding web 55 vwhich traverses the space between the top and bottom walls and which merges into both thereof. The vbolster `is additionally reinforced l*at its interior-by transversely extending `webs56 which are located within .the reduced Uend porti-ons l5 and which merge into the 7bottom wall and also into the sides. There is no 'necessity for continuing vthe beveled surfaces 48 and49 beyond these webs 56.

The bolster is of course intended to traverse the space between the truck side frames with its ends 15 received within the usual window openings so as to be supported by the nests or clusters .of springs. The opposite vsides of the bolster are therefore formed with laterally `projecting lug-s 57 'backed' up by inclined brace webs 58 and adapted to cooperate with the inner faces of Athe side vframes for the purpose of preventing the bol' ster from shifting longitudinally. As. this bolster is intended primarily for use in a truck in which the ordinary spring plank is eliminated it is preff erablethat these lugs be of greatersize than cus.,- tomary so as 'to increase the bearing area and consequently reduce the wear on the column guidesand on the lugs themselves.

:For lassisting in taking the lateral or lend thrust and also to insure the proper squared relation of the bolster with respect tof the'side frames, vrecourse maybehad to the same 'scheme' of .construction and arrangement disclosed in said co-pendingapplication but for thesake ofv clearness this feature is shown and described .in this case. The bolster preferably has each end portio'n'formed with openings 59 in its opposite sides, the top and bottom being partially cut awayas indicatedat 60 and 6l respectively, the material remaining between the side edges and these cut awa-y portions 60 and 61 constituting flanges" 62 which are connected by tiesvor webs 63 of reduced thickness, so as to be capable of bending for instance as the result' of a blow from a sledge hammer. To avoid the use of additional cores in casting, these ties are preferably joined at their outer edges to the sides of the bolsteri Extending transversely through the openings 59 vis a retaining member 64 of channel 'shape in cross section having vertical webs 65 located outwardlyof the bendable webs 63. When the bolster yis assembled in a truck, to effect positive securing the member 64 is inserted through'the openings 59 in each 'end of the bolster, subse quently to which the webs 63 are'forced or bent inwardly as indicated by the full lines in Figure 2, these webs then projecting vinwardly ofthe bolster in obstructing relation to the verticalwebs 655011 the-transverse member 64 so that the lat-l tercannot move transversely of the bolster; Fur* thermore this inward bending of the webs 63 will tend to draw the anges 62 toward each other into close gripping or clamping relation to the member 64, thereby holding the same against any looseness or rattling.

Thebolster is intended particularly 1for use in the type of truck shown inthe above-mentioned co-'pending application and it will be seen that the .truck may be `constructed simply of three partsnamely the two side frames and the bolster, the transverse members 64 being considered a part ofy the former. nating' the spring plank have been carefully pointed out in said co-pending application and need not be herein` repeated. Omitting the spring plank makes it possible to use a bolster of much-greater depth or heightthan is ordinarily the case and it is for this reason 'that I have shown myimproved bolster as of much greater depth at its center, the depth being in fact so great that if a spring plank were used it would interfere -with the bolster. Of coursethe height The advantages of elimif might be reduced so that the bolster could be used in a truck in which the spring plank is present, as this single feature does not detract from the other advantages of my bolster construction. Squaring of the bolster with respect to the side frames is effected by means of the greater length of bearing of the vertical ends of the bolster coacting with the increased width of side frame column guides. Throughout every portion of the bolster it will be observed that the detailed formation is such as to insure maximum strength with minimum weight. This is particularly to be observed in connection with the corner formation, the beveling of the top and sides at the inner surfaces and the similar beveling of the sides at the bottom providing increased thickness of metal at these points of strain. The beveling and thickening arrangement is such that the thickest part of the metal will be where the bottom of the bolster merges into the reduced end portions, it being well known that the shear lines are concentrated at this locality. Provision has been made to eliminate undue length of the side compression members so that they will not buckle under the most severe strains. In fact it is believed that a bolster constructed in this manner Will have the greatest possible durability in service.

From the foregoing description and a study of the drawings it is believed that the construction, operation and advantages will be readily apparent to one skilled in the art without further explanation.

While I have shown and described the preferred embodiment of the invention, it should be understood that the disclosure is merely an exemplication of the principles involved as the right is reserved to make all such changes in the details of construction as will widen the eld of utility and increase the adaptability of the device provided such changes constitute'no departure from the spirit of the invention or the scope of the claims hereunto appended.

Having thus described the invention, I claim:

l. A truck bolster comprising a single cast body including a top, a bottom and side walls, the sides and the top wall being inclined on their inner surfaces at their junctures to provide greater thickness than that of the top or the side walls for reinforcing purposes.

2. `A truck bolster comprising top, bottom and side walls, and having both the side and top walls beveled to provide increased thickness.

3. A railway car truck bolster comprising top, bottom and side walls, the juncture of the top and side walls being rounded at the exterior along a curve of relatively large diameter, and the inner surfaces of the top and side walls being ybeveled at their juncture to increase the thickness of the metal at their junctures.

4. A railway car truck bolster comprising top, bottom and side walls, the latter converging downwardly, the inner faces of the side walls being beveled or angular and converging downwardly at the junctures of the side walls with the bottom to increase the thickness of metal at the lower longitudinal edges, the metal between the edges being of substantially uniform thickness.

5. A railway car truck bolster comprising a single cast body including a top, bottom and side walls, the latter converging downwardly, the bottom wall being convex at the center and inclined upwardly toward points spaced inwardly from the ends whereby said ends will be of reduced heightfor disposition upon spring nests in side frames, the bottom wall'being of gradually reduced thickness from the ends of the inclined portion to the intermediate portions of said reduced ends, and webs formed on the sides and merging into the bottom at said intermediate portions.

6. A railway car truck bolster comprising a smgle cast body including a top, bottom and side walls, the latter converging downwardly, the bottom wall being convex at the center and inclined upwardly toward points spaced inwardly from the endsv whereby said ends will be of reduced height for disposition upon spring nests in side frames, the bottom Wall being of gradually reduced thickness from the ends of the inclined portion to the extremities, the inner surfaces of the top and sides being formed to increase the thickness at the longitudinal upper edges.

7. A railway car truck bolster comprising a single cast body including a top, bottom and side walls, the latter converging downwardly, the bottom wall being convex at the center and inclined upwardly toward points spaced inwardly from the ends whereby said ends will be of reduced height for disposition upon spring nests in side frames, the bottom wall being of gradually reduced thickness from thefends of the inclined portions to the extremities, the inner surfaces of the top and sides being formed to increase the thickness at the longitudinal upper edges, the maximum cross sectional thickness of metal in proportion to the cross sectional area of the bolster being at the junctures of the inclined portions of the bottom wall'with said reduced end portions.

8. A truck bolster formed as a single cast body comprising a'top, a bottom and side walls, the latter converging downwardly, an upright thrust member extending between and merging into the top and bottom at the center of the bolster, a center bearing formed on the center of the top, said thrust memberbeing formed interiorly with transverse reinforcing webs, and a plurality of horizontally disposed webs merging into the exterior of said thrust member'and into the sides.

9. A truck bolster formed as a single cast body comprising a top, a bottom and side walls, the latter converging downwardly, an upright thrust member extending between and merging into the top and bottom at the center of the bolster, a center bearing formed on the center of the top, said thrust member Vbeing formed interiorly with transversey reinforcing webs, a plurality of hori- Zontally disposed webs merging into the exterior of said thrust member and into the sides, anda plurality of inclined reinforcing webs merging into the exterior of said thrust member at the lower portion thereof and into said bottom.

10. A railway truck bolster formed as a single casting and including'a top, a bottom and sides connecting the same, a centrally located thrust member connecting the top and bottom and connected by horizontal pairs of webs with the sides, the top having an upstanding ilange concentric with the center of said thrust member for receiving the center 'plate of a body bo-lster, and ribs formed on the top and extending from the side edges thereof in converging relation toward the vertical axis of the bolster and merging into said flange.

11. A bolster formed as a single cast body comprising a top, a bottom and sides connecting the same, a vertically extending hollow thrust member at the center connecting the top and bottom, the opposite sides being formed outwardly of but adjacent said thrust member with openings having their upper and lower edges substantially parallel with the top and bottom, the metal between the openings and the top defining compression members, the metal between the openings and the top being prolonged downwardly at an angle at the inner ends of the openings to reduce the beam length of the compression members.

12. A bolster formed as a single cast body comprising a top, a bottom and sides connecting the same, a vertically extending hollow thrust member at the center connecting the top and bottom, the opposite sides being formed with openings at said thrust member and being also formed outwardly of but adjacent said thrust member with other openings provided at their upper edges with continuous beads common to both, the metal between the openings and the top defini-ng compression members, the metal between the openings and the top being prolonged downwardly below the bead at the inner ends of the openings to reduce the beam length of the compression members. f

13. A bolster formed as a single cast body comprising a top, a bottom and sides connecting the same, a vertically extending hollow thrust member at the center connecting the top and bottom, the opposite sides being formed outwardly of but adjacent said thrust member with. openings whereby the metal between the openings and the top will denne compression members, the metal between the openings and the top being prolonged downwardly at the inner ends of the openings to reduce the beam length of the compression members, the metal at the outer ends and upper edges of said openings being thickened to denne reinforcing beads, and the lower corners of the bolster having thickened portions coinciding with the lower edges of the openings.

14. A bolster formed as a single cast body cornprising a top, a bottom and sides connecting the same, a vertically extending hollow thrust member at the center connecting the top and bottom, the opposite sides being formed outwardly of but adjacent said thrust member with openings spaced downwardly from the top whereby the metal between the openings and the top will define compression members, the metal between the openings and the top being prolonged downwardly at the inner ends of the openings to reduce the beam length of the compression members, the metal at the ends and upper edges of said openings being thickened to denne reinforcing ribs, said ribs extending `across the vertical center of the inner faces of the side walls.

15. A bolster comprising a body formed as a single cast body including a top, a bottom and sides connecting the same, the top being formed as a center bearing, a vertical thrust member located at the center and connecting the top and bottom beneath said center bearing, said thrust member being spaced from the sides and connected thereto by intermediately located transverse webs, the sides being formed opposite the center with openings and being formed with other openings spaced outwardly from said rst named openings, and a rib formed on the inner surface of each side and extending from the outer ends of the second named openings, along the upper edges thereof, and across the space intervening between said second named openings and across the top of the rst named openings.

16. A bolster formed as a single cast body comprising a top, a botto-m and sides connecting the same, a center bearing at the center of the top,

ter bearing, a vertical thrust taking member connecting the top and bottom beneath said center bearing, ribson the top merging into the center bearing for diverting. a portion of the high compression strain to the center bearing, the top and sides being formed with a plurality of openings with the material at the edges thereof thickened to provide reinforcing ribs, the ribs at the openings in the sides extending continuously along the sides from one side of the vertical axis to the other. .f

18. A bolster comprising a single cast body including a top, a bottom and sides connecting the same, the top being formed centrally withy a center bearing, a vertical thrust taking member connecting the top and bottom beneath said center bearing, ribs on the top merging into the center bearing for diverting a portion of the' high compression strain toI the center bearing,

the top and sides being formed with a plurality of openings with the material at the edges thereof thickened to provide reinforcing ribs, the ribs at the openings in the sides extending continuously along the sides from one side of the vertical axis to the other, the material at the inner ends of the openings in the sides being prolonged downwardly below said last named ribs to shorten the effective beam length of the compression members defined between the openings in the sides and the top.

19. A bolster formed as a single cast body comprising a top, a botttom and sides connecting the same, a vertically extending hollow thrust member at the center between the sides and connecting the top and bottom, the sides having openings spaced downwardly from the top, whereby the metal at the top of said opening forms the compression member and the metal below said opening forms the tension member, the metal between the openings and the top being prolonged downwardly at the inner ends of the openings to reduce the beam length of the compression members, the metal at the ends and upper edges of said openings being thickened to denne reinforcing ribs, said ribs extending across the vertical center of the inner faces of the side walls.

20. A railway car truck bolster comprising a top, botttom and side walls, the junctures of the top and bottom with the side walls being rounded at the exterior along a curve of relatively large diameter, the inner surfaces of the top and side walls being bevelled to increase the thickness of the metal at their juncture, the inner surfaces of the bottom and side walls being bevelled near the ends of the bolster at their juncture to increase the thickness of the metal at this junction point.

21. A truck bolster comprising top, bottom and side walls, and having the inner faces of its side and top and bottom walls bevelled at their respective junctures to provide increased thickness.

22. A truck bolster formed as a single cast body comprising a top, a bottom and sides connecting the same, a vertically extending hollow thrust member at the center connecting the top and bottom, the opposite sides being formed outwardly of but adjacent said thrust member with openings spaced farther downwardly from the top than upwardly from the bottom, the sides being formed with beads at the upper edges of said openings, said openings having their upper and lower edges parallel with the top and bottom of the bolster. Y

23. A truck bolster formed as a single cast body including top, bottom and sidewalls, the top being formed centrally with an upstanding flange constituting a center bearing, a vertical thrust member connecting the top and bottom beneath said center bearing, webs formed on rthe bottom wall and merging into the thrust member, transverse ties connecting the thrust member with the sides of the bolster, and a horizontal brace member extending across the interior of said thrust member and having at its transverse center line spaced webs merging into its bottom and into the sides of the thrust member.

24. A bolster comprising a single cast body including a top, bottom and sides connecting the same, the top being formed centrally with a center bearing, a vertical thrust member connecting the top and bottom beneath said center bearing, said thrust member being formed at an intermediate I point with a horizontal tie trough shaped in cross section and being formed above and below the same with weight reducing openings, horizontal webs connecting the intermediate portion of the thrust member with the sides, diagonal webs merging into the sides and the lower portion of the thrust member at the exterior thereof, and vertical webs located within the thrust member and merging into the sides thereof and into said tie.

25. A bolster comprising a single cast body including a top, a bottom and sides connecting the same, the top being formed centrally with a center bearing, a vertical thrust member connecting the top and bottom beneath said center bearing and spaced from the sides thereof, the sides being formed beyond said thrust member with elongated openings, the sides being each formed with a continuous bead extending from the outer ends of said openings, along the upper edges thereof and across the intermediate portion of the bolster.

` 26. A bolster comprising a single cast body including a top, a bottom and sides connecting the same, the top being formed centrally with a center bearing, a vertical thrust member connecting the top and bottom beneath said center bearing and spaced from the sides thereof, the sides being formed beyond said thrust member with e1ongated openings, the sides being each formed with a continuous bead extending from the outer ends of said openings, along the upper edges thereof and across the intermediate portion of the bolster, said side walls being further provided each witha thickened portion below said openings extending continuously from the outer ends thereof across the intermediate portion of the bolster.

27. A truck bolster comprising a single cast body including a top, a bottom and sides connecting the same, the bolster being of greatest depth at its center and having its bottom inclined upwardly toward the ends and continued substantially horizontally to the ends defining an angle, the side walls being each formed with a beveled inner surface adjacent its juncture with the top to provide the maximum cross sectional thickness of material at said angle, said beveled surfaces extending part way of the length of the substantially horizontal end portions.

28. A truck bolster comprising a single cast body including a top, a bottom and sides connecting the same, the bolster being of greatest depth at its center and having its bottom inclined upwardly toward the ends and continued substantially horizontally to the ends dening an angle, the side walls being each formed with a beveled inner surface adjacent its juncture with the top to provide the maximum cross sectional thickness of material at said angle, said beveled surfaces extending part way of the length of the substantially horizontal end portions, and a vertically extending web connecting the top and bottom adjacent said angle.

THOMAS H. SYMINGTON 

